TOKYO—Honda and Nissan on Thursday officially scrapped their planned merger less than two months after announcing it, putting pressure on troubled Nissan to look for other partnerships.The two Japanese automakers had said in December that they planned to combine operations by 2026,

The Japanese companies’ decision to call off negotiations highlights the challenges legacy automakers face in partnering to tackle new technologies.

Japanese auto giants Honda and Nissan confirmed they've scrapped merger talks announced in December​, ending a tie-up that would have created the world's third-largest automaker.